[s3e16] Infernal Guinea — Pig

Pierce believes Abel is the key to breaking his curse. However, the episode concludes with a darkly ironic twist: just as the brothers find a moment of peace, Abel is killed by a stray ambulance, leaving Pierce trapped in his immortality once again. Guilt and Redemption: Charlotte Richards

Abel is revealed to be the "infernal guinea pig" on whom the demons of Hell practiced their torture for millennia. [S3E16] Infernal Guinea Pig

While the celestial beings deal with resurrection, Charlotte Richards undergoes a deeply human transformation. Struggling with memories of her time in Hell, she begins therapy with Dr. Linda. Pierce believes Abel is the key to breaking his curse